When two wave pulses moving in opposite directions completely cancel each other as they pass, it means that they are undergoing a phenomenon known as wave interference. In the case of complete cancellation, it is referred to as destructive interference.
During destructive interference, the peaks of one wave align with the troughs of the other wave, resulting in their amplitudes summing up to zero. As a result, the wave pulses effectively cancel each other out at specific points in space and time.
While the amplitudes cancel each other, it's important to note that the energy associated with the waves does not simply vanish or disappear. Energy is a conserved quantity, meaning it cannot be created or destroyed but can only be transferred or transformed.
During destructive interference, the energy of the wave pulses is redistributed rather than being eliminated. The energy that was present in the waves gets redistributed into other forms or areas. In the case of the wave pulses canceling each other, the energy is typically redistributed as heat or other forms of non-mechanical energy.
For example, if the wave pulses are traveling on a string, the energy of the waves can be dissipated as heat in the string or the surrounding medium. In the case of sound waves, destructive interference can result in reduced sound intensity at specific locations, with the energy being dispersed as heat in the medium.
It's important to remember that destructive interference only occurs when specific conditions are met, such as the waves having the same amplitude and frequency, and being in phase opposition. In other scenarios, partial cancellation or different interference patterns may occur, leading to different outcomes in terms of energy redistribution.